Can external current pass through Faraday cage,like thunder?

[Physicsissuef]

Can external current pass through Faraday cage,like thunder? Will be there electrical field, inside the Faraday cage?

 

[Shooting Star]

In the ideal case, the Faraday cage should be an unbroken hollow conducting shell. Then there cannot be any electrical field inside due to outside fields. In practice, it is made of fine mesh, and connected to the ground, that is earthed.

A heavy duty properly grounded cage will prevent lightning from passing through. But, theoretically, it's possible to imagine an exceptionally powerful bolt of lightning entering it, because it's a mesh, not an unbroken hollow shell.

 

[astrokreng]

I can confirm that external current cannot pass through a Faraday cage, much like thunder. A Faraday cage is designed to block external electromagnetic fields and currents, providing a shielded environment. This is achieved through the principle of electrostatic shielding, where the conductive material of the cage redistributes the external electric fields and cancels them out inside the cage.

Therefore, any external current, such as lightning or electrical surges, will be unable to pass through a Faraday cage. However, it is important to note that the effectiveness of a Faraday cage depends on its design and construction. A poorly constructed cage may not provide complete protection against external currents.

As for the presence of an electrical field inside the Faraday cage, it will depend on the source of the external current. If the external current is induced by an electric field, then there may be a small electrical field inside the cage. However, it will be significantly weaker than the external field due to the shielding effect of the cage. If the external current is due to a magnetic field, then there will be no electrical field inside the cage.

In conclusion, a Faraday cage is an effective tool for blocking external currents and fields, providing a safe environment for sensitive equipment or experiments. However, it is crucial to ensure that the cage is properly constructed and grounded to provide maximum protection.